The phrase, according to Rolfe's lawyer David Edwardson QC, is one that is "taught, trained and drilled" into NT Police officers and is frequently used among the NT Police force.

"In other words, where a police officer is confronted with an edged weapon, the appropriate response is to draw your weapon and be prepared to use it," Mr Edwardson told the court during his opening address on Tuesday.

"That expression 'edged weapon equals gun' will loom large and ripple through almost all the police witnesses in this case."

Mr Rolfe, 30, faced the second day of his murder trial in the Darwin Supreme Court on Tuesday. The charge stems from the shooting death of the 19-year-old Mr Walker in the NT Aboriginal community of Yuendumu in 2019.

READ MORE:

Mr Rolfe has pleaded not guilty to murder as well as to two alternative lesser charges.

The court heard Rolfe was a member of the NT Police's Immediate Response Team (IRT), which was deployed from Alice Springs to Yuendumu to arrest Mr Walker who had breached a court order by fleeing a residential rehab centre in Alice Springs to go home for his great uncle's funeral.

When Rolfe and his partner, Constable Adam Eberl, found Mr Walker inside a house and went to arrest him, he pulled out a pair of surgical scissors and stabbed Mr Rolfe in the shoulder who then shot him in the chest area.

After Constable Eberl had wrestled Mr Walker to the ground, Mr Rolfe deployed two more gunshots in close succession into his back. It is the second and third gunshots which are the subject of the criminal charges, with the first being seen a legally justified by the prosecution.

Mr Walker died from his injuries around an hour later.

Mr Edwardson told the court when Mr Rolfe deployed these shots, he was simply following that mantra that had been drilled into him.

"It will be the defence case through the various prosecution witnesses that are to be called that Constable Zachary Rolfe did no more than respond in the way in which he had been trained," he said.

"That shot was in response to Mr Walker's deployment of the edged weapon against Constable Rolfe before, on the defense case, turning his attention to Constable Eberl."

The first prosecution witness of the trial, Alice Springs based Police officer Sergeant Robert Kent, was among the officers tasked with finding and arresting Mr Walker when he first fled the Alice Springs rehab.

When asked by Mr Edwardson in cross-examination, Sgt Kent agreed he had been trained that "blade equals gun" which means officers should draw their firearm and "be prepared to use it" if threatened with an edged weapon.

However, in re-examination by counsel assisting the prosecution Sophie Callan SC, he said there would be a number of steps taken before actually firing.

"Verbal commands would be the first you'd go through, hand on your firearm is an escalation. Drawing your firearm is an escalation. Pointing your firearm is an escalation. Firing your firearm is again, an escalation."

Earlier in the day, the court heard during Crown prosecutor Philip Strickland SC's opening address that Mr Rolfe did not warn either Mr Walker or Officer Eberl before firing off three shots.

"The accused did not give any warning to Kumanjayi Walker or Eberl he was about to use his Glock. He didn't shout anything - he didn't shout, "Knife - knife - knife" or "Scissors - scissors - scissors". - didn't direct Walker to drop them and Detective Barram [a prosecution witness] will say the police are trained to give such warnings - or commands - in those situations," Mr Strickland said.

He also showed jurors footage from body worn cameras on the five members of the IRT, including Mr Rolfe, on the night of Mr Walker's death.

Referring to one piece of footage, Mr Strickland said a member of the community approached Officer Eberl, and asked why another member of the team was openly carrying a gun without a holster, saying "he's got it like aimed to shoot someone".

"He was probably referring to Hawkings [a team member] who was carrying an assault rilfle - it's the AR15." Mr Strickland told the court.

Mr Strickland told the court Officer Eberl replied: "Someone probably shouldn't run at police with an axe."

He said the comment was presumably a reference to an incident three days earlier where local police attempted to arrest Mr Walker, but fled when he came at them with a small axe.

Mr Strickland also referred to the footage from the moments after Mr Walker had been shot and was lying on a mattress on the floor, moaning in pain and calling out for his mother, as well as threatening to kill the officers.

As he did so Mr Rolfe told his partner: "He was stabbing me. He was stabbing you".

Mr Rolfe had a "small puncture wound" to his left shoulder.

Mr Strickland suggested to the jury that Mr Rolfe may have said those words "because he knew he had gone too far".

"He knew the shots were not necessary or reasonable. He knew everything he had done was captured on the body worn video," he said.

"In short he said those words to justify what he'd done."

The trial continues.

With AAP.

If you are seeing this message you are a loyal digital subscriber to The Katherine Times, as we made this story available only to subscribers. Thank you very much for your support and allowing us to continue telling your stories. We appreciate your support of journalism in our great area.

Our journalists work hard to provide local, up-to-date news to the community. This is how you can continue to access our trusted content:

DO YOU HAVE SOMETHING TO SAY?: Send letters to the editor or story tips to editor.kathtimes@austcommunitymedia.com.au